Pumping system



Dec. 5, 1950 .1. w. M CONAGHY PUMPING SYSTEM Filed Nov. 24, 1948 39 so2o- INVENTOR JameSWMt'lbnay/z H15 ATTORNEY.

efficiently under such conditions.

Patented Dec. 5, 1950 I UNITED sures mum OFFICE v I PUMPING srs'rrar jJames w. McConaghy, minimum,- n.1, 03-

signor .to

Ingersoll-Band Company, New York,

N. Y.', a corporation of New Jersey I Application November 24, ms,Serial No. 61,190

be utilized where the source of the fluid-bein pumpedisintermittent.

, Heretofore, it has been impracticable to use centrifugal pumps underconditions where the 1 Claim- (Cl. res-s) ated and its outlet ordischarge It connected to flow of fluid being pumped may be interruptedof the positive displacement pump, as compared to the centrifugal pump,it is highly desirable to have a centrifugal pump which will operate Itis, accordingly, one object of this invention to construct a pumpingsystem which utilizes centrifugal pumps and is capable of continuous andefllcient operation under conditions where the source of the fluid beingpumped is intermittent.

, in that such interruptions resulted in the loss of municated' with thesource of fluid to be evacuinlet I! of the centrifugal pump Ii. --Withthis arrangement, it is readily apparent that by maintaining a waterlevel in the tank I! sumcient-to flll the pump l2, the pump I2 willatall times be self priming and, therefore, capable of continuous orintermittent operation, as desired; and, further, with .thisarrangement, the

Another object of this inventionis to provide a pumping system in whichthe danger of loss of prime of the pump is obviated regardless of theflow of the fluid to be evacuated.

A still further object of this invention is to construct a pumpingsystem which is unusually compact and eflicient.

Further objects of this invention will become obvious from the followingspecification and accompanying drawing in which,

Figure 1 is a vertical elevation of a pumping system constructed inaccordance with -the1practice of the invention and adapted to evacuatefluid from a well,

Fig. 2 is a vertical'elevation, partly in section, of a centrifugal unitadapted to a pressure tank, and r I Fig. 3 is a vertical elevation,partly in section, of a jet pump utilized in cooperation with thecentrifugal unit to evacuate fluid from a shaft or other source wherethe flow of fluid to be pumped may be intermittent.

Referring to the drawing, l0 ing system having a pair of'coaxiallymounted centrifugal pumps I l-IZ connected in series i. e., thedischarge of one pump being communicated with the inlet of thesucceeding pump, through the pressure tank I3. In the present instance,

the pump H discharges into the pressure tank motivate a jet pump Mhaving itsinlet l5 compump I! will serve to s pply fluid to the pump IIfor priming purposes irrespective of the flow of fluid to be evacuatedby the jet pump ll. Thus, whenever the centrifugal unit is operating,the jet' pump it will be supplied with motive fluid ,and the system, asa whole, will coact effectively to evacuate fluid from a source whereinthe flow of fluid is intermittent-as for example, under conditions suchas exist .in mines wherein it is desired to evacuate water seepage fromthe mine. Under these circumstances, the centrifugal unit is located ata considerable distance below the surface of the earth depending, ofcourse, on the pressure developed in the tank H by the centrii'ugal pumpII. The jet pump H is located at a point below the centrifugal unit at alow point in the mine where water seepage tends to collect. Sopositioned, the jet pump l l serves to boost or pump such-water seep ge,mixed, of course, with the motive fluid, up to the centrifugal unitwherein fluid is removed from that portion of the system connecting the,centrifugal pumps in seriesnamely, the pressure tank l3, according tothe 7 amount of fluid evacuated and passes it through a conduit 5|,connected in the top of the pressure.

tank II, to the surface for discharge from the system.

More specifically the pumping system comprises a pressure tank l3 onwhich is mounted a casing casing IS. The housin 2| is provided with andesignates apumpinternal flange 22, having a central perforation 23,which encircles and provides a bearing surface for the motor drivenshaft 24 extending into the housing 2|. Relative rotation between theshaft 24 and the impellers l9 and 20, journaled on the lower end 'of theshaft, is prevented by means of a nut 25 threaded on the end of theshaft 24 and bearing against the lower end of the impeller 20 which, inturn, forces the impeller l9 into frictional engagement with a shoulder26 on the shaft 24. Leakage of fluid along the shaft 24 into the upperportion of the housing 2| is prevented by a seal 21, of well knownconstruction, mounted in the pump a cup shaped extension or projection28 on the upper surface of the flange 22.

The lower surface of the flange 22 cooperates with inwardly extendingprojection 29 on the housing 2| to define the inlet l1, and with a plate30 mounted athwart the housing 2| between the impellers l9 and 20 todefine the impeller chamber 3| for the pump II. The chamber 32 for theimpeller I2 is formed between the lower surface of the plate 30 and acover 33 secured to the lower end of the housing 2| by a suitable meanssuch as the bolts 34. 1

Depending from and integrally with the cover 33 is a tubular extension35 having its lower or free end 36 encircling an opening 31 in the lowerportion of the tank l3 and secured to the tank l3 by means of bolts 38.The extensiori35 in cooperation with the shell 39 extending out from thehousing 2| from a line adjacent the impeller l3, defines a channel 40'between the centrifugal unit and the pressure tank I3. In order toprevent turbulence in the fluid entering the pump l2, a partition 4| isprovidedwithin the channel 40 which separates the channel into an inletpassage 42 for the pump 2 and an outlet passage 43 for the pump I; andto further minimize any turbulence in the inlet passage 42 and to permitair to escape from the fluid before entering the passage 42, the loweror free end 44 of the partition 4| extends into the tank 3 and is curvedupwardly to direct the flow of fluid from the first stage impeller I9away from the inlet 42, or that portion of the tank I3 from which thepump l2 drains fluid.

The jet pump I4 of the usual construction and comprising a nozzle 45which is arranged to direct a high velocity jet of fluid, deliveredthereto from the outlet 52 of the pump l2 through a conduit 46 threadedin the nozzle inlet passage 53, into a difiusor 41 which, in turn, isccmmunicated with the inlet I! of the pump through a conduit 48. Thefluid to be evacuated or pumped by the system is conducted to the jetpump I 4 through a nipple 49 threaded at one end in the inlet 50 of thejet l4 and at the other end in a valve means, as shown, the foot valvewhich is submerged in the fluid to be evacuated and serves to preventfluid frcm drainingfrom the conduits 46 and 48 when the pumping unit isnot in operation.

In construction, the distance which the jet pump I4 is located below thepump I2 is determined, of course, by the design of the pump |2 that is,the jet pump l4 must, at all times, be able to force fluid through theconduit 48 to the pump Assuming the water level in the pressure tank I3is as shown in Figure 2 and that the foot valve-5| is submerged, uponstarting the centrifugal unit the pump 2 will develop a predeterminedpressure differential across the impeller and supply fluid foractivating the jet l4 which, in turn, will pump fluid from the sump toprime The pump H, in turn, will develop a predetermined pressuredifferential across the impeller l9 and thereby increase the pressureexisting in the tank l3 which increases the pressure at the inlet of thepump l2. Thus, it may be seen, a regenerative cycle is obtained whichwill permit the discharge pressure of the pump l2 to increase, due toincreasinginlet pressure, until a stable condition has been reached. Thepressure within the tank l3 will be the discharge pressure of the pumpthereby making available a source of pressure for boosting or liftingthe fluid to be evacuated to a point above the tank before beingdischarged from the system. When the supply of fluid to be evacuated isexhausted, the discharge pressure of the pump II will decrease due tothe decrease in flow and the discharge pressure of the pump l2 will,accordingly, decrease and the flow of fluid throughout the system willbe determined by the amount of fluid needed to operate the jet, or, inother words, the amount of fluid that passes through the nozzle 45.

It is now obvious from the previous discussion that the presentinvention provides an unusually simple and compact pumpingsystem whichaccomplishes, among others, the object hereinbefore referred to.

While I have shown andslescribed a specific form of my invention, it isto be understood that various changes and modifications may be madewithout departing from the spirit of the invention as set forth in theappended claim.

I claim:

A pumping system comprising a high pressure pump, a low pressure pumpsuperposed on the high pressure pump, a jet pump located adjacent thesource of liquid to be pumped, a conduit for conveying the discharge ofthe high pressure pump to the jet pump to form the jet, a conduit forconveying the discharge of the jet pump to the intake of the lowpressure pump, a tank having an inlet opening and an outlet opening,said outlet opening adjacent to and below the inlet opening, a conduitto convey the discharge from the low pressure pump to the inlet openingof the tank, a conduit to convey liquid from the outlet opening of thetank to the intake of the high pressure pump, and means in the tankadjacent the inlet opening to deflect the discharge of the low pressurepump away from the outlet opening.

JAMES W. MCCONAGHY.

REFERENCES CITED The following references are of record in the flle ofthis patent:

UNITED STATES PATENTS

